Autism Explained

(also known as pervasive developmental disorder)

Autism, a Complex Disorder

Autism is a complex developmental disorder that appears in the first three years of life, although it is sometimes diagnosed much later. It affects the brain's normal development of social and communication skills.

  • Autism is a spectrum that includes a wide range of behavior.
  • The common features include impaired social interactions, impaired verbal and nonverbal communication, and restricted and repetitive patterns of behavior.
  • The symptoms may vary from moderate to severe.
  • Causes, incidence, and risk factors

  • Autism is a physical condition linked to abnormal biology and chemistry in the brain. The exact causes of these abnormalities remain unknown. There are probably a combination of factors that lead to autism.
  • Genetic factors seem to be important; for example, identical twins are much more likely than fraternal twins or siblings to have autism.
  • Similarly, language abnormalities are more common in relatives of autistic children.
  • Chromosomal abnormalities and other neurological problems are also more common in families with autism.
  • A number of other possible causes may involve digestive tract changes, diet, mercury poisoning, vaccine sensitivity, and the body's inefficient use of vitamins and minerals.
  • The exact number of children with autism is not known, but estimates suggest that roughly one in one-thousand children are affected.
  • Autism affects boys three to four times more often than girls.
  • Family income, education, and lifestyle do not seem to affect the risk of autism.
  • Some doctors attribute the increased incidence in autism to newer definitions of autism.
  • The term "autism" now includes a wider spectrum of children; for example, a child who is diagnosed with high-functioning autism today may have been thought to simply be odd or strange thirty years ago.
  • Some symptoms can be observed by parents

  • Most parents of autistic children suspect that something is wrong by the time the child is eighteen months old and seek help by the time the child is two years old.
  • Children with autism typically have difficulties in verbal and nonverbal communication, social interactions, and pretend play.
  • In some, aggression (toward others or self) may be observed.
  • Some children with autism appear normal before one or two years old and then suddenly "regress" and lose the language or social skills that they had previously gained. This is labeled as an "regressive type" of autism.
  • People with autism may perform repeated body movements, show unusual attachments to objects, or have unusual distress when routines are changed.
  • Individuals may also experience sensitivities in the senses of sight, hearing, touch, smell, or taste.
  • Such children, for example, will refuse to wear "itchy" clothes and become unduly distressed if forced because of the sensitivity of their skin.
  • Some combinations of the following areas may be observed in varying degrees:


    1. Unable to start or sustain a social conversation.
    2. Develops language slowly or not at all.
    3. Repeats words or memorized passages, like commercials.
    4. Doesn't refer to self correctly; for example, he/she says "you want water" when the child means "I want
    5. Uses nonsense rhyming.
    6. Communicates with gestures instead of words.

    Social reactions

    1. Shows a lack of empathy.
    2. Does not make friends.
    3. Is withdrawn.
    4. Prefers to spend time alone, rather than with others.
    5. May not respond to eye contact or smiles.
    6. May actually avoid eye contact.
    7. May treat others as if they are objects.
    8. Does not play interactive games.

    Response to sensory information:

    1. Has heightened or low senses of sight, hearing, touch, smell, or taste.
    2. Seems to have a heightened or low response to pain.
    3. May withdraw from physical contact because it is overstimulating or overwhelming.
    4. Does not startle at loud noises.
    5. May find normal noises painful and hold hands over ears.
    6. Rubs surfaces, mouths or licks objects.

    When Playing:

    1. Shows little pretend or imaginative play.
    2. Doesn't imitate the actions of others.
    3. Prefers solitary or ritualistic play.


    1. Has a short attention span.
    2. Uses repetitive body movements.
    3. Shows a strong need for sameness.
    4. "Acts up" with intense tantrums.
    5. Has very narrow interests.
    6. Demonstrates perseveration (gets stuck on a single topic or task).
    7. Shows aggression to others or self.
    8. Is overactive or very passive.

    Warning signs:

    All children should have routine developmental exams by their pediatrician. Further testing may be needed if there is concern on the part of the clinician or the parents.

    This is particularly true whenever a child fails to meet any of the following language milestones:

    1. Babbling by twelve months.
    2. Gesturing (pointing, waving bye-bye) by 12 months.
    3. Single words by 16 months.
    4. Two-word spontaneous phrases by 24 months (not just echoing).
    5. Loss of any language or social skills at any age.

    Children with known or suspected autism will often have genetic testing (looking for chromosome abnormalities) and perhaps metabolic testing.

    Autism encompasses a broad spectrum of symptoms. Therefore, a single, brief evaluation cannot predict a child's true abilities. Ideally, a team of different specialists will evaluate the child.

    They might evaluate speech, language, communication, thinking abilities, motor skills, success at school, and other factors.

    Additional considerations

    Beware that there are widely publicized treatments for autism that do not have scientific support, and reports of "miracle cures" that do not live up to expectations.

    If your child has autism, it may be helpful to talk with other parents of children with autism, talk with autism specialists, and follow the progress of research in this area, which is rapidly developing.

    Expectations or prognosis:

    Autism remains a challenging condition for individuals and their families, but the outlook today is much better than it was a generation ago. At that time, most people with autism were placed in institutions.

    Today, with appropriate therapy, many of the symptoms of autism can be improved, although most people will have some symptoms throughout their lives. Most people with autism are able to live with their families or in the community.

    The outlook depends on the severity of the autism and the level of therapy the individual receives.

    Complications that may occur:

    1. Autism can be associated with other disorders that affect the brain, such as tuberous sclerosis, mental retardation, or fragile X syndrome. Some people with autism will develop seizures.
    2. The stresses of dealing with autism can lead to social and emotional complications for family and caregivers, as well as the person with autism.

    —Compiled from internet sources; including:
    MedlinePlus, and Parent's Common Sense Encyclopedia.

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